Stephen M. Omohundro

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We describe a framework for inducing probabilistic grammars from corpora of positive samples. First, samples are incorporated by adding ad-hoc rules to a working grammar; subsequently, elements of the model (such as states or nonterminals) are merged to achieve generalization and a more compact representation. The choice of what to merge and when to stop is(More)
This paper describes PicHunter, an image retrieval sys­ tem that implements a novel approach to relevance feedback. It uses Bayesian learning based on a probabilistic model of a user's behavior. The predictions of this model are com­ bined with the selections made during a search to choose the images to display. The details of our model were tuned using an(More)
This report describes a new technique for inducing the structure of Hidden Markov Models from data which is based on the general 'model merging' strategy (Omohundro 1992). The process begins with a maximum likelihood HMM that directly encodes the training data.' Successively more general models are produced by merging HMM states. A Bayesian posterior(More)
One might imagine that AI systems with harmless goals will be harmless. This paper instead shows that intelligent systems will need to be carefully designed to prevent them from behaving in harmful ways. We identify a number of “drives” that will appear in sufficiently advanced AI systems of any design. We call them drives because they are tendencies which(More)
This paper addresses how the effectiveness of a content­ based, multimedia information retrieval system can be mea­ sured, and how such a system should best use response feed­ back in performing searches. We propose a simple, quan­ tifiable measure of an image retrieval system's effective­ ness, "target testing", in which effectiveness is measured as the(More)
ion de ned by that type. With multi-methods code does not naturally belong to a particular type. Sather deals with multi-method situations by using \typecase" statements. These appear in the body of a routine which dispatches on the rst argument type and may explicitly dispatch on the second argument type. Unlike a simple \case" statement applied to the(More)
A technique for representing and learning smooth nonlinear manifolds is presented and applied to sev­ eral lip reading tasks. Given a set of points drawn from a smooth manifold in an abstract feature space, the technique is capable of determining the structure of the surface and of finding the closest manifold point to a given query point. We use this(More)